Scope & closures

Question 1

Tokenizing / lexing

Answer 1

Breaking up a string of characters in source code into meaningful chunks.

Question 2

Parsing

Answer 2

Taking a stream (array) of tokens and turning it into a tree of nested elements, which collectively represent the grammatical structure of the program. This tree is called the “Abstract Syntax Tree”, or AST.

Question 3

Code-generation

Answer 3

The process of taking an AST and turning it into executable code. This process will vary greatly depending on the language, the platform it’s targeting, etc.

Question 4

Scope

Answer 4

The set of rules that determines where and how a variable (identifier) can be looked up.

Question 5

LHS lookup

Answer 5

A lookup for the purposes of assigning a value to a variable.

Question 6

RHS lookup

Answer 6

A lookup for the purposes of retrieving the value stored in a variable.

Question 7

The type of error thrown on unfulfilled RHS lookups (when in strict mode)

Answer 7

ReferenceError

Question 8

The type of error thrown on unfulfilled LHS lookups

Answer 8

TypeError